"How successful is the open source content management system
(CMS) Drupal? Well, in a recent interview, Drupal founder Dries
Buytaert noted that nearly 790,000 people in 228 countries
contribute to the platform, and it powers more than a million
online sites. The White House, NASA and Twitter use it, and OStatic
is also built on Drupal. In an interview we did with Buytaert, he
described the core contributors to the project as on the "same
scale as the Linux kernel."
"Getting started with Drupal can be daunting at first, but there
are a lot of free resources for it. Here several good ways to get
going with this powerful CMS."